Transition-Metal-Free Poly(thiazolium) Iodide/1,8-Diazabicyclo[5.4.0]undec-7-ene/Phenazine-Catalyzed Esterification of Aldehydes with Alcohols
作者:Supill Chun、Young Keun Chung
DOI:10.1021/acs.orglett.7b01617
日期:2017.7.21
Poly(3,4-dimethyl-5-vinylthiazolium) iodide was used as a polymer precatalyst in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and phenazine for the oxidative esterification of aldehydes with alcohols. Selective functionalization of OH groups was achieved in the presence of NH2 groups. The poly(thiazolium) iodide/DBU/phenazine system exhibited excellent catalytic activity and could be reused
Nickel-Catalyzed Cross-Coupling of Aryl Redoxactive Esters with Aryl Zinc Reagents
作者:Bo-Hao Shih、R. Sidick Basha、Chin Fa Lee
DOI:10.1021/acscatal.9b02913
日期:2019.10.4
reaction conducted using a redox active ester with aryl zinc reagent was developed. This method demonstrates a new disconnection approach for formation of arylaryl esters. In the one-pot sequential process, the readily available aryl carboxylic acids can be converted into functionalized arylaryl esters and heteroaryl esters. This protocol is amenable to the gram-scale synthesis. The present method
The first example of a palladium-catalyzed aerobic oxidative coupling of acyl chlorides with arylboronic acids has been developed, leading to a wide range of aryl benzoates in good to excellent yields. This catalytic system shows broad functional group tolerance. Preliminary mechanistic experiments using deuterium labeling showed that the oxygen atom was derived from dioxygen.
Determination of aromaticity indices of thiophene and furan by nuclear magnetic resonance spectroscopic analysis of their phenyl esters
作者:Chang Kiu Lee、Ji Sook Yu、Hye-Jin Lee
DOI:10.1002/jhet.5570390615
日期:2002.11
series of m- and p-substituted phenyl benzoates, 2-thienoates, and 2-furoates were prepared and their 1H and 13C nmr spectroscopic characteristics were examined. In general, good correlations were observed between the chemical shift values of protons and carbons of the acyl aromatic rings and the Hammett σ. Plots of the chemical shift values of the carbonyl carbons of the benzoates against those of
A simple and direct aerobic oxidativeesterification reaction of arylacetonitriles with alcohols/phenols is achieved in the presence of a copper salt and molecular oxygen, which produces a broad range of aryl carboxylic acid esters in good to high yields. Copper salt plays multiple roles in the transformation, which allows the oxygenation of CH bond, cleavage of inert CC bond, and formation of CO